They're snickering at our naivete...because we refuse to see their British humor of their silliness.

Honestly, no one is that sincerely stupid without the need of a lot of psycho tropic drugs, therapy (perhaps the temporary, but ugly necessity of a straitjacket) and maybe a lot of lemming-like leaping off the wide variety of cliffs in jolly old England and the other places like Wales, Ireland, etc...because in the unlikely event, they actually mean this knife business they're all bonkers and may as well do themselves a favor and leap...